The present invention relates to a vehicle-body side portion structure of a vehicle, and in particular to a vehicle-body side portion structure of a vehicle, which includes a center pillar comprising an outer panel, an inner panel, and a first reinforcement panel provided between the outer panel and the inner panel.
At a vehicle-body side portion of a vehicle, such as an automotive vehicle, is provided a center pillar extending in a vehicle-body vertical direction at a position between front and rear door openings. The center pillar is generally formed by an outer panel forming a vehicle-body outside and an inner panel forming a vehicle-body inside so as to have a closed cross section.
A center pillar additionally equipped with a reinforcement panel which is provided inside its closed cross section formed by its outer panel and its inner panel for increasing strength and rigidity thereof is used widely as well. As this kind of reinforcement panel, a first reinforcement panel which is provided between the outer panel and the inner panel and a second reinforcement panel which is joined to the first reinforcement panel are also known.
Japanese Patent Laid-Open Publication No. 2009-262614, for example, discloses a center pillar, in which both-side vertical wall portions of a second reinforcement panel having a cross section formed in substantially a U shape are joined, by welding, to both-side vertical wall portions of a first reinforcement panel having a cross section formed in substantially a hat shape, and a bottom wall portion formed between the both-side vertical wall portions of the second reinforcement panel is joined, by welding, to a bottom wall portion of a protrusion portion of the first reinforcement panel.
In the center pillar disclosed in the above-described patent document, the second reinforcement panel is joined to the first reinforcement panel at the bottom wall portion and the both-side vertical wall portions of the second reinforcement panel. Therefore, an accuracy of dimensions may be required to the both-side vertical wall portions of the second reinforcement panel.
FIG. 8 is a view showing a center pillar of a conventional vehicle body, and FIG. 9 is a sectional view of the center pillar taken along line Y9-Y9 of FIG. 8. A center pillar 100 shown in FIGS. 8 and 9 extends in a vehicle-body vertical direction at a position between front and rear door openings 3, 4, and its upper end is joined to a roof rail 5 and its lower end is joined to a side sill 6.
The center pillar 100 comprises, as show in FIG. 9, an outer panel 101 comprising a bottom wall portion 101a, both-side vertical wall portions 101b, and both-side flange portions 101c and having a cross section formed in substantially a hat shape, an inner panel 102 comprising a bottom wall portion 102a, both-side vertical wall portions 102b, and both-side flange portions 102c and having a cross section formed in substantially a hat shape, and a first reinforcement panel 103 comprising a bottom wall portion 103a, both-side vertical wall portions 103b, and both-side flange portions 103c and having a cross section formed in substantially a hat shape. Herein, these flange portions 101c, 102c, 103c are joined together in a state in which the first reinforcement panel 103 is provided between the outer panel 101 and the inner panel 102. Thereby, the center pillar 100 is formed so as to have a closed cross section.
Additionally, a second reinforcement panel 104, which comprises a bottom wall portion 104a and both-side vertical wall portions 104b and has a cross section formed in substantially a U shape, is provided inside the first reinforcement panel 103. The second reinforcement panel 104 is provided inside the first reinforcement panel 103 such that the bottom wall portion 104a and the both-side vertical wall portions 104b of the second reinforcement panel 104 substantially match the bottom wall portion 103a and the both-side vertical wall portions 103b of the first reinforcement panel 103, respectively, and the second reinforcement panel 104 is joined to the first reinforcement panel 103 such that the bottom wall portion 104a and the both-side vertical wall portions 104a of the second reinforcement panel 104 are respectively joined, by spot welding, to the bottom wall portion 103a and the both-side vertical wall portions 103b of the first reinforcement panel 103 at positions indicated by x marks in FIG. 9.
In this case in which the second reinforcement panel 104 is joined to the first reinforcement panel 103 at its bottom wall portion 104a and its both-side vertical wall portions 104b, it is required that a specified gap is provided between the both-side vertical wall portions 104b of the second reinforcement panel 104 and the both-side vertical wall portions 103b of the first reinforcement panel 103 at the spot welding in order to obtain an appropriate joint quality. Thus, an accuracy of dimensions is required to the both-side vertical wall portions 104b of the second reinforcement panel 104.
In a case in which the distance between the both-side vertical wall portions 104b of the second reinforcement panel 104 is shorter than a specified distance, the gap between the both-side vertical wall portions 104b of the second reinforcement panel 104 and the both-side vertical wall portions 103b of the first reinforcement panel 103 becomes large, so that the appropriate joint quality cannot be obtained. Consequently, there is a concern that a reinforcing effect by the second reinforcement panel 104 may not be effectively obtained.
In the case in which the distance between the both-side vertical wall portions 104b of the second reinforcement panel 104 is shorter than the specified distance, by setting the gap between one of the vertical wall portions 104b of the second reinforcement panel 104 and one of the vertical wall portions 103b of the first reinforcement panel 103 at the specified gap, the appropriate joint quality can be obtained for the above-described one of the vertical wall portions 104b of the second reinforcement panel 104. In this case, however, the gap between the other of the vertical wall portions 104b of the second reinforcement panel 104 and the other of the vertical wall portions 103b of the first reinforcement panel 103 becomes large, so that the appropriate joint quality cannot be obtained. Accordingly, it becomes necessary that the second reinforcement panel 104 is modified or disused. This may cause deterioration of productivity at the time of vehicle-body manufacturing.
Meanwhile, in a case in which the distance between the both-side vertical wall portions 104b of the second reinforcement panel 104 is longer than the specified distance, there is a concern that the second reinforcement panel 104 inserted into the first reinforcement panel 103 may not be joined to the first reinforcement panel 103. In this case, likewise, it may be necessary that the second reinforcement panel 104 is modified or disused, and this may cause deterioration of productivity at the time of vehicle-body manufacturing.
In particular, in a case in which the second reinforcement panel 104 is made of a high-tension steel plate which is formed by pressing, since it is difficult to ensure the accuracy of dimensions due to a large spring back occurring after the press forming, the necessity of modifying or disusing the second reinforcement panel 104 increases more in order to obtain the stable joint quality. This may further cause the problem of productivity at the time of vehicle-body manufacturing.